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181.
Rai PK 《Environmental monitoring and assessment》2012,184(1):113-131
The present article provides a multifaceted critical research review on environmental issues intimately related with the socio-economy
of North East India (NE), a part of Indo-Burma hotspot. Further, the article addresses the issue of sustainable development
of NE India through diverse ecological practices inextricably linked with traditional ecological knowledge (TEK). The biodiversity
of NE India comprises endemic floral diversity, particularly medicinal plants of importance to pharmaceutical industry, and
unique faunal diversity. Nevertheless, it is very unfortunate that this great land of biodiversity is least explored taxonomically
as well as biotechnologically, probably due to geographical and political constraints. Different anthropogenic and socio-economic
factors have perturbed the pristine ecology of this region, leading to environmental degradation. Also, the practice of unregulated
shifting cultivation (jhooming), bamboo flowering, biological invasions and anthropogenic perturbations to biodiversity exacerbate the gloomy situation.
Instead of a plethora of policies, the TEK of NE people may be integrated with modern scientific knowledge in order to conserve
the environment which is the strong pillar for socio-economic sector here. The aforesaid approach can be practiced in NE India
through the broad implementation and extension of agroforestry practices. Further, case studies on Apatanis, ethnomedicinal plants use by indigenous tribal groups and sacred forests are particularly relevant in the context of conservation
of environmental health in totality while addressing the socioeconomic impact as well. In context with the prevailing scenarios
in this region, we developed an eco-sustainable model for natural resource management through agroforestry practices in order
to uplift the social as well as environmental framework. 相似文献
182.
The presence of natural estrogen hormones as trace concentrations in the environment has been reported by many researchers
and is of growing concern due to its possible adverse effects on the ecosystem. In this study, municipal biosolids, poultry
manure (PM) and cow manure (CM), and spent mushroom compost (SMC) were analyzed for the presence of seven estrogen hormones.
17α-estradiol, 17β-estradiol, 17α-dihydroequilin, and estrone were detected in the sampled biosolids and manures at concentrations
ranging from 6 to 462 ng/g of dry solids. 17α-estradiol, 17β-estradiol, and estrone were also detected in SMC at concentrations
ranging from 4 to 28 ng/g of dry solids. Desorption experiments were simulated in the laboratory using deionized water (milli-Q),
and the aqueous phase was examined for the presence of estrogen hormones to determine their desorption potential. Very low
desorption of 0.4% and 0.2% estrogen hormones was observed from municipal biosolids and SMC, respectively. An estimate of
total estrogen contribution from different solid waste sources is reported. Animal manures (PM and CM) contribute to a significant
load of estrogen hormones in the natural environment. 相似文献
183.
Fernandes CE Das A Nath BN Faria DG Loka Bharathi PA 《Environmental monitoring and assessment》2012,184(5):2677-2689
We investigated the influence on bacterial community and biochemical variables through mechanical disturbance of sediment-akin
to small-scale mining in Kalbadevi beach, Ratnagiri, a placer-rich beach ecosystem which is a potential mining site. Changes
were investigated by comparing three periods, namely phase I before disturbance, phase II just after disturbance, and phase
III 24 h after disturbance as the bacterial generation time is ≤7 h. Cores from dune, berm, high-, mid-, and low-tide were
examined for changes in distribution of total bacterial abundance, total direct viability (counts under aerobic and anaerobic
conditions), culturability and biochemical parameters up to 40 cm depth. Results showed that bacterial abundance decreased
by an order from 106 cells g − 1 sediment, while, viability reduced marginally. Culturability on different-strength nutrient broth increased by 155% during
phase II. Changes in sedimentary proteins, carbohydrates, and lipids were marked at berm and dune and masked at other levels
by tidal influence. Sedimentary ATP reduced drastically. During phase III, Pearson’s correlation between these variables evolved
from non-significant to significant level. Thus, simulated disturbance had a mixed effect on bacterial and biochemical variables
of the sediments. It had a negative impact on bacterial abundance, viability and ATP but positive impact on culturability.
Viability, culturability, and ATP could act as important indicators reflecting the disturbance in the system at short time
intervals. Culturability, which improved by an order, could perhaps be a fraction that contributes to restoration of the system
at bacterial level. This baseline information about the potential mining site could help in developing rational approach towards
sustainable harnessing of resources with minimum damage to the ecosystem. 相似文献
184.
Nagaraja P Prakash JS Asha SC Bhaskara BL Kumar SA 《Environmental monitoring and assessment》2012,184(10):5983-5988
A rapid, simple, accurate, and sensitive visible spectrophotometric method for the determination of trace amounts of hydrogen peroxide in acidic buffer medium is reported. The proposed method is based on the oxidative coupling of Ampyrone with dibenzazepin hydrochloride by hydrogen peroxide in the buffer medium of pH?4.0 which is catalyzed by ferrous iron. The blue-colored product formed with maximum absorption at 620?nm was found to be stable for 2?h. Beer's law is obeyed for hydrogen peroxide concentration in the range of 0.03-0.42?μg?ml(-1). The optimum reaction conditions and other important optical parameters are reported. The molar absorptive and Sandell's sensitivity are found to be 5.89?×?10(4)?mol(-1)?cm(-1) and 0.57?g/cm(2), respectively. The interference due to diverse ions and complexing agents was studied. The method is successfully applied to the determination of hydrogen peroxide in green plants satisfactorily. 相似文献
185.
Seasonal variation in heavy metal contamination in water and sediments of river Sabarmati and Kharicut canal at Ahmedabad, Gujarat 总被引:3,自引:0,他引:3
Rita N. Kumar Rajal Solanki J. I. Nirmal Kumar 《Environmental monitoring and assessment》2013,185(1):359-368
The objective of the study is to reveal the seasonal variations in the river water and sediment quality with respect to heavy metal contamination. To get the extent of trace metals contamination, water and sediment samples were collected from five different sites along the course of Sabarmati River and its tributary Kharicut canal in pre-monsoon, monsoon and post-monsoon seasons. The concentration of trace metals such as chromium, copper, lead, nickel and zinc was determined using inductively coupled plasma spectroscopy. The concentrations of heavy metals were found to be higher in the pre-monsoon season than in the monsoon and post-monsoon seasons in water samples. The pollution load index, contamination factor and degree of contamination (C d) in sediments were calculated to know the extent of anthropogenic pressures. The values of C d clearly indicated very high degree of contamination at Kharicut canal (S-4: 32.25 and S-5: 54.52) and considerable degree of contamination at three sites of Sabarmati river viz; S-1, S-2 and S-3 with values 14.30, 14.42 and 17.21, respectively. Lead and nickel could not be traced in any of the river water samples. 相似文献
186.
Mike Williams Anupama Kumar Christoph Ort Michael G. Lawrence Adam Hambly Stuart J. Khan Rai Kookana 《Environmental monitoring and assessment》2013,185(11):9321-9332
The assessment of potential impacts of wastewater effluent discharges in freshwater systems requires an understanding of the likely degrees of dilution and potential zones of influence. In this study, four tracers commonly present in wastewater effluents were monitored to compare their relative effectiveness in determining areas in freshwater systems that are likely to be impacted by effluent discharges. The four tracers selected were the human pharmaceutical carbamazepine, anthropogenic gadolinium, fluorescent-dissolved organic matter (fDOM), and electrical conductivity (EC). The four tracers were monitored longitudinally in two distinct freshwater systems receiving wastewater effluents, where one site had a high level of effluent dilution (effluent <1 % of total flow) and the other site had a low level of effluent dilution (effluent ~50 % of total flow). At both sites, the selected tracers exhibited a similar pattern of response intensity downstream of discharge points relative to undiluted wastewater effluent, although a number of anomalies were noted between the tracers. Both EC and fDOM are non-specific to human influences, and both had a high background response, relative to the highly sensitive carbamazepine and anthropogenic gadolinium responses, although the ease of measuring EC and fDOM would make them more adaptable in highly variable systems. However, the greater sensitivity and selectivity of carbamazepine and gadolinium would make their combination with EC and fDOM as tracers of wastewater effluent discharges highly desirable to overcome potential limitations of individual tracers. 相似文献
187.
188.
A. V. M. Subba Rao Arun K. Shanker V. U. M. Rao V. Narsimha Rao A. K. Singh Pragyan Kumari C. B. Singh Praveen Kumar Verma P. Vijaya Kumar B. Bapuji Rao Rajkumar Dhakar M. A. Sarath Chandran C. V. Naidu J. L. Chaudhary Ch. Srinivasa Rao B. Venkateshwarlu 《Environmental Modeling and Assessment》2016,21(1):17-30
189.
Alka Sharma Rita Kumar Anil Kumar S. V. Gangal 《Environmental monitoring and assessment》2000,60(3):251-260
A number of microorganisms were isolated from sewage. Biochemical Oxygen Demand (BOD-5 day) analysis was carried out by individual pure cultures. The cultures giving higher or equal BOD values as compared to reference GGA solution were selected for the formulation of a defined mixed microbial consortium. This microbial consortium was co-immobilized on calcium-alginate beads. Four synthetic and six industrial samples were tested for BOD by using immobilized beads as well as sewage as source of seeding materials. BOD values obtained with beads for all the synthetic as well as industrial samples were fairly comparable with those obtained with sewage. Reusability of prepared microbial beads was also checked with different synthetic and industrial samples and was compared with reference GGA solution. The same microbial beads can be reused three times for different BOD-5 day estimations. It is recommended that immobilized microbial beads can be used as a ready-to-use seeding material for BOD analysis. 相似文献
190.
Nagaraj P Aradhana N Shivakumar A Shrestha AK Gowda AK 《Environmental monitoring and assessment》2009,157(1-4):575-582
A simple and sensitive spectrophotometric method for the determination of chromium has been developed. The method is based on the diazotization of Dapsone in hydroxylamine hydrochloride medium and coupling with N-(1-Napthyl) Ethylene Diamine Dihydrochloride by electrophilic substitution to produce an intense pink azo-dye, which has absorption maximum at 540 nm. The Beer's law is obeyed from 0.02-1.0 microg mL(-1) and the molar absorptivity is 3.4854 L mol(-1) cm(-1). The Limits of quantification and Limit of detection of the proposed method are 0.0012 microg mL(-1) and 0.0039 microg mL(-1) respectively. The method has been successfully applied for the determination of chromium in water samples and the results were statistically evaluated with that of the reference method. 相似文献